It is the third time Trump and Putin have spoken over the telephone since the former took office.

As well as involvement in Syria, the leaders discussed working together to tackle tensions with North Korea, a White House statement adding the pair discussed dealing with "how best to resolve the very dangerous situation" there.

Trump and Putin are expected to meet over the summer, potentially at the G20 summit.

Their phone call came as Putin spoke with German chancellor Angela Merkel during her trip to Russia, with conversation topics including violence against gay men in Chechnya.